Short-acting insulin

Replaced by insulin analogues as the quickest acting insulins.

Often known as soluble or ‘regular’ or 'neutral' insulin.

Some features of short-acting or neutral insulins include:

• peak 2-6 hours after subcutaneous injection
• tendency to form hexamers in the insulin vials - these dissociate slowly leading to reduction in absorption rate
• onset of action 30–60 mins
• peak 2–4 hours
• in some individuals can have an effect 8-12 hours after administration of injection
• injected 20-30 minutes before a meal
• may result in postprandial and nocturnal hypoglycaemia because of long-lasting effects
• in some patients short-acting insulins remain the optimum quick-acting insulin
• examples Human Actrapid®, Humulin S®, Insuman® Rapid? (also porcine and bovine equivalents of these)
• note that some of these insulins are also licensed for use in continuous subcutaneous insulin infusion i.e. insulin pumps (1)

Examples include human actrapid.

Reference:

1. MeRec Bulletin 2007;17(4).
2. Prescriber 2001;12 (14): 43-50